# CVE-2026-94543: Next.js: Cache poisoning of SSG and ISR pages in self-hosted Next.js applications

> Attackers can poison the cache of self-hosted Next.js Pages Router applications, causing visitors to receive incorrect content from different routes.

- **Severity:** Medium 6.3 (`CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 2 Oct 2026
- **Updated:** 6 Oct 2026
- **Also known as:** CLEANSTART-2026-LV87996, CLEANSTART-2026-QE81238, CLEANSTART-2026-XH75311, CLEANSTART-2026-YH35813, CLSA-2026-1792195721, CLSA-2026-1792196714, CLSA-2026-1792206282, CLSA-2026-1792256959, CLSA-2026-1792272219, CLSA-2026-1792292992, CLSA-2026-1792304708, CLSA-2026-1792326287, CLSA-2026-1792338226, CLSA-2026-1792346463, CLSA-2026-1792358580, CLSA-2026-1792363976, CLSA-2026-1792367382, ECHO-8ef5-f166-2c7c, GHSA-4jqv-mc3x-m676, MINI-3qw7-6f34-82v6, MINI-8cx3-rh3r-q9c7, MINI-fg7r-5mm9-grw4, MINI-q5c9-59gh-hhj5, ROOT-APP-NPM-CVE-2026-94543

## What is CVE-2026-94543?

CVE-2026-94543 is a medium-severity vulnerability in Vercel Next.js, published on 2 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Next.js is a React framework for building full-stack web applications. From 15.0.0 until 15.5.27 and 16.3.8, self-hosted applications using the Pages Router with statically generated or Incremental Static Regeneration pages can key a response cache entry without sufficiently binding it to the source route. A request can replace one page's cache entry with content from a different route, causing the affected page to serve incorrect content to every visitor until revalidation. Applications deployed on Vercel are not affected. This issue is fixed in versions 15.5.27 and 16.3.8.

Weakness: CWE-524 (Use of Cache Containing Sensitive Information)

## Which versions are affected by CVE-2026-94543?

4 open source packages ship an affected version, including next. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `next` | npm | From 15.0.0 | 15.5.27 |
| `next` | npm | From 15.0.0 | 15.5.27 |
| `next` | npm | From 16.0.0 | 16.3.8 |
| `next` | npm | From 16.0.0 | 16.3.8 |

Products: Vercel Next.js.

## How do I fix CVE-2026-94543?

Upgrade next to a fixed version for your release line: 15.5.27 or 16.3.8.

## Is CVE-2026-94543 being exploited?

There is no known exploitation of CVE-2026-94543 in the wild and no public exploit code.

## Other vulnerabilities in Vercel Next.js

- [CVE-2025-29927](https://insights.sbomify.com/CVE-2025-29927/): Authorization Bypass in Next.js Middleware (critical 9.1)
- [CVE-2026-44578](https://insights.sbomify.com/CVE-2026-44578/): Next.js: Server-side request forgery in applications using WebSocket upgrades (high 8.6)
- [CVE-2026-94483](https://insights.sbomify.com/CVE-2026-94483/): Next.js: Server-Side Request Forgery in Image Optimization (high 8.3)
- [CVE-2026-64642](https://insights.sbomify.com/CVE-2026-64642/): Next.js: Middleware / Proxy bypass in App Router applications using Turbopack and single locale (high 8.3)
- [CVE-2026-64645](https://insights.sbomify.com/CVE-2026-64645/): Next.js: Server-Side Request Forgery in rewrites via attacker-controlled destination hostname (high 8.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-94543 and fix it if it is affected.

What it is: CVE-2026-94543 is a medium-severity vulnerability in Vercel Next.js, published on 2 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-94543 in the wild and no public exploit code.

Affected packages and fixed versions:
- next (npm): affected from 15.0.0; fixed in 15.5.27
- next (npm): affected from 15.0.0; fixed in 15.5.27
- next (npm): affected from 16.0.0; fixed in 16.3.8
- next (npm): affected from 16.0.0; fixed in 16.3.8

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-94543/ (Markdown: https://insights.sbomify.com/CVE-2026-94543/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-94543
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-94543
- OSV: https://osv.dev/vulnerability/CVE-2026-94543

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-94543/
Summaries are generated and may contain mistakes; the official description above is the record.